2.3 Shoot & Leaf Growth Flashcards
When is Shoot and Leaf Growth in the Northern Hemisphere?
March–July
When is Shoot and Leaf Growth in the Southern Hemisphere?
September–January
What is Shoot and Leaf Growth?
When the shoots continue to grow, and leaves and inflorescences (a cluster of flowers on a stem) mature.
When does the fastest rate of shoot and leaf growth occur?
The fastest rate of growth generally occurs between budburst and flowering
What initially supports shoot growth?
- Initially: Carbohydrates stored in the roots, trunk and branches of the vine support the initial shoot growth.
What eventually supports shoot growth?
- As leaves develop and mature, they provide energy for further growth via photosynthesis, and therefore need adequate warmth and sunlight for this to take place.
What 4 factors might contribute to low carbohydrate levels?
- Excessive leaf removal
- Water stress
- Mildew infections
- High crop loads in the previous growing season
What main problem can occur during shoot and leaf growth? Why is this problematic?
Water stress
- Can limit photosynthesis and shoot growth
- Can limit nutrient uptake through the roots
What does stunted shoot growth lead to?
- Small, weak shoots
- A reduction in leaf number or smaller leaves
- Inflorescences that do not flower properly
- Grape bunches that do not ripen fully
- Poor quality
- Lower yields
What does the vine needs during this stage? What are some adverse conditions?
What the vine needs during this stage:
- Stored Carbohydrates
- Warmth, sunlight, nutrients and water
Adverse conditions:
- Low carbohydrate levels (caused by conditions in the previous growing season)
- Water stress